Mechanical fuse for artillery projectiles



Dec. 11, 1928. L695,070

A. VARAUD MECHANICAL FUSE FOR ARTILLERI PROJECTILES Filed June 17, 1925 2 Sheets-Sheet 2 I I H30 I w 0'2 24 24 75 8 m;

' tion are threefold: p p v v1. To considerably reducethe motivepower a AnDnE' v nAnn, orIGEnEvA; sWITZER AnnQ-Q i/incrninrcanrusn sop. linrrnnnnrlrnoancrrtnsg Application file d iune'ikzfiees;seriaino szecs; stain; swifze'najn mrgast 2 ,1923; 1

This invention relates to clockworkv operated fuses for artillery projectiles of the type in whichv the release or"unlocking iof thei strikeris controlled by a rotary settingfmem her, the angular position of which can be set before .firing and which duringtlieflight of the projectile is driven by a clockwork having a power spring in a-direction' o'p'po-j site tothe one in which the setting is effected. In one prior construction OftlllS type it has been proposed to provide a pivoted disk' -con trolling the striker and adaptedto be re-r leased by .a rotary crown member lntegral with the spring drum of the fuse and with an 4 internally toothed portiondriving the escapement regulating mechanism of the fuse. 1

As shown and described in'my copending' application Serial Number 38,498, filed June 20, 1925, it is proposed'to mechanically cone nect a rotary set memberflto thedrive shaft of the clockwork of the'fuse by fme'a'ns ofa reducing gear. The .obj ects of. this 'construcf required for striker.

2 To enablethe drive shaft of the clock: work mechanism to perform several winding.

' revolutions for 'ones'etting revolu'tionof the: rotary setting member and to consequently reduce the required multiplication between the drive shaft and the last moving member of the gear train of the clockwork mechanism, that is to saythe escapementwhe'el.

3. To increase the'motive power storage capacityof the main spring ofthe fuse;

The apparatus made in accordance with my present lnvention preferably cons sts 1n;

the combination of a rotary setting member in the form of an internally toothedmember,

or crown piece with a reduction gear conneot I 7 ing the drive shaft'of theclockwork thereto.

The attached drawing represents .bv my 7 of example one embodimentof theobjectof" V U n 9 by that ofvthei centrifugal 'forceby minim- V f I the invention. v

line II of FigJQQ -;Figs. 2 to 4 are crosssections" on the lines I-a IV IV respectively f Fig. 5 isa similar section as that shown in.

I Fig. 4: showing the position of the retaining reration f thp latr member of th er at the momentof libi, "Intlie drawing which shows onlyfthose f This'strikerfis normally locked in its cocked one hal'foffits transverse section. "Thislockresistance which the percussion spring-f3 :exj'

The Figures, 11 and lens Vesta se tidn J on alarger scaleion the line VI-Vlotlfig the partsof the'fuse which are"directlyfasso v 'ciatedf withfthe objecthof the invention',jit;

will be seenthatthe strikerl is. guided new;

its" whole length'n' a 'sleeve'2and is subjected'.*

tothe action of a strong percussion s rin 3 surrounding the'lsleeve 2 and acting on acol -l V lar or shoulder presented'byfthe striker near 7 f' The subjectmatter ofFigs. 1 to'5 inclusive. 1 i is shown an'dd'escribed in my copending ape? plication', SerialjNo; 7l2,960' filed May 1'3,"

1 position (Figs. land 4) bya retaining meme; 1 berorbolt 4'," taking intofa lateral notcha fi pro vided for intheistriker body overjabolit T c s" bolt efiis-p t y n bou the .85 i shank of a stopjscrew' 6 and is 'subjected-to'f' the action. of a pulling-01f 'spnn rbearingg in t a'r nifii t Il sp rpeh el er yf' from'the belt at so as"to (counterbalanceQthei 3i 19 ,7 ertson-this bolt'l; v V. Up to the moment offiringthebolt4 0 V mally held in its locking posit ion aigaijnstfthe i bf pr nsiibyie d' op plug'ii ffit ed withyaspring'sle'eve l of'a'nd adapted to {drop 9. J f v out of position 'injalwell known manner-by. i

the whole flight ofith'e projectilethisboltfj v is 'retainedqin'itsactiye orlocking p ition againsttheactionof the spring 7 thenaided 1 0 0 inertia a theinornenti 'offiring, smea in f piece ll'issuppdrtdl JTh'e lippereceorsaid' 541 I 'iF g- 10% 0 3 iSf hownindottedlines); v 7 i piece 11; v. V v 2 v 7' In thecylindrical edgeofthevcrownpiece I alevel vvith thebolt 4c; V I l p I V V t The unlocking or liberationot the striker J pmion 21 keyed on thelower extremity ofthe driveshaft 22 of the fuse; The'ratios of the gears 17,18, and 21 are such as to enable I the driving shaft- 22 to perfornrseveral rev-. olutlons' for a s nglerev0lut-1on-of the crown 11 against which a nose 24'otthe 1ocking bolt 4'con1esto hear at themon ent ofthe Ldepan, V tureof the projectile is provided aslot 23 011 g 1' takes place when this slot 23 happens-tof with a catch 26 projecting radially towards register With'the nose 2 L of bolt 4.

Ehe crown piece 11 is in addition provided its center and cooperating witlrlthe drop. plug v e or iveighted pin'i) 4) to preventup to the m-olnent of firing any; .rotation. of the toothed crownin clockwise direotion,;that is to say for rendering impossible any accidental unlocking of the striker. i I

In order to avoid, in thelcase that the pro jectile to Whichlthe fuse, isf'applied, were dropped during its transport or-handling,

that the drop-plug for eighted pin 9 isnot accidentally Withdrawn, a notch :9, (Figsivlg -Y and 4;) is provided for inthehead of said pin, into Which the catch26 is engaged at the termination ofthel inanufactureofthe fuse in'such amanner'as to th ereby render any accidental displacement of the drop=plug or I eighted pin'9 impossible, as "long as the v .Inechanism of the striker is as fol lovvs; l i

7 On the'winding of the'p ower spring 27 of catch26 has not been displaced in the come tear-clockwise direction, thatis tosay as long as the fuse has not been tin ed. p

The function of. this. release or unlocking the clockwork movement offthe fuse the toothed crownineinber lIis driven to rotate in counter-clockwise edirection tl'lrough an angle in proportion to the duratlon offiight a which t 1s deslred to be obtained. 9 T1115 an gle,as in the case or several of known me chanieal fuses, cannot. attain 360, b.utf contrary towhat ex st in prlor fuses-.o.vv1ng to l the reduction gear'2l, 2O and l8, I7, this'fact does not prevent'the main shaft. 22 froniper er i s s wlw d e u onso In such a manner llllS POSS1bl6 to' store the poweri-spri'ngJZT a motive power,

Whichfis' sufficient to"obtainfiringranges of relatively JVerygreat durations, and to subdivide these durationsinto. a very largejnunr.

her-oft setting positions for difierent ranges.

, (ishoyvn i n Figs'l anew, a

I It should be observedthatduring the re the latter is enabled 7 easy manner.

l-force, liberatesinstantaneously the striker Itisto be noted that the-tact of em loying Moreover, also owing to this demultiplicw tion, the effort of the motive power required .forrcontrolling therelease or unlocking or thestriker-1e cons lembly reduced as co1npared with known fuses in which the rotary controlling In'emb'erz-o'f the unlocking of the striker is integral ivith the driving member of the'clockwork movement.

VJ-hilstthis counter-clockwise rotation of the crown rnernber lltakes place which rota-V tionfldeterinines the setting or the time for the ignition ofthelfuse the bolt i and the drop? plug or we ghted. leverfi remain stationary in the r respective operat ve .posltlons Winding" and thesiinultaneous setting of the fuse thus efiect-edf thenose 24 of the'bolt .4 is'not inicon'tact with-the crovvnill, whereby to be rotatedinavery A t theniornent of firing the dropplug, or"

pin?) disappears inits container in the known manner byjlnertia and the nose 2a comes to bear againstthe interior face of thecrown '11 Which-thereupon is dr ven by the clock- VWOI'k movement to return 1.111 clockwise d1rection through t'heftravel traversed but. in oppos te senseduringlts sett ng travel ncreased, however, by the s nall" angle required for bringing" the notch "23jtro1n' the position according'to Fig. l, to the release position asfsliown in Fig"; 5;

r p e having reached this latter? position, the boltl, under the combined "ael'J IOl'l'Of II J SSPTlHg 'T an'd of thefcentrlitu'gal ill the crown with an internal soothing l? pernnts to utilize for this member, the diain eterof which is'to be as large" as possible nearly the Whole space at disposal in the inte- I rior of'thejbodyoi the fuse; v

Since the friet ion b'etwven the nose r le gand,v the rown 11, during the operation of the clockwork-isproportional tothe angular ve- V locity of the :projectile,i' asthe lever issub jected tothe actionoi'thecentrifugal'foree,% itjlnay prove useful in the case that the fuse is fitted to a projectile of, a great angi'llar velocityi to' employ intermediate member Yvvhich prevents any directQconta'ct tee-ween the nose 24 and'the crown 11 during many the entire trajectory Wh lst said direct con tact may be established affew noinents before the arrivalof the notch 23jopposite thenoser 24:. In this manner the pe'werz-requiredfor driving the crown 11' is considerably, reduced Wliileth'e devicepreservesitsgprecision as re 'gards the release of the striker.

""Accordingfto theFigs. 6 and 7;. the

mediate [nienibercomprises a hook 128, lnountedso as tooscillate aboutithestriker l. This hook holds normally the lever oiut of contact fronithe crown ll'owing ,toa notch 27 in which the pin 8 normally is-lodged while the striker 1 is in'cocke'd' positions The arrangement is such that during the operation? notch 23 comes oppositeand permits-the libs,

eration of the striker 1.

According to the second constructional form as shown in Figs. 8 to 12, the hooki28 of the first form is replaced by apin 29 mounted freely in the frame ofthe clockwork. This pin 29 is held in its operative position by a spring 31 and ing this position retains by its'endBOthe nose 24 of the lever 4; spaced from the crown. In order to disene gagethe lever r from the pin 29,;the latteris v provided with an inclined plane 32-,against which the pawl 26 of the crown operates at the moment in whichitcomes: to registerwith the pin. v I p Owing to this action the pin 29 withdraws and is displaced in a perpendicular plane in regard to lever 4: and abandons the latter to the actionof its spring and of the centrifugal force. Since this liberation of the lever 4 by the pin- 29 is'eifeoted some hundredths of a second before the notch 23 arrives'opposite the nose 24:, the contact ofi this noseon the periphery of the crown takes place only-dur- I ,to-determine the moment of releasepfthei ing this infinitely short period of time a fact from which results the'nearly complete sup pression of thefperturbating causes-of the operation of the clockwork which n'pcto now,

have been due to the friction ofthe locking device of the striker.

Besides, in order to progressively dimin ish the retaining surface of therleve'r t with regard to the striker until the momentof the release, the internal border of the crown is progressively made thinner as at 33, so. as to constitute on theside ofthe notch an'in clined plane on which the nose of thislever slides. V V

lVhat I claim is: 1

1. In a projectile of the type described, drive shaft, a revoluble member a: striker, a locking device for normally maintaining determined portion of a revolution inthe.

other direction 'to determine the 1noment;of release ofthe striker, means for normally maintaining the lOcking-memberOut of con- ,before the release: of the. stri er, and means "the sa me to .coo'perate with the revoluble T to; 'afs"et positionfand 'whent hedrive shaft; 5 V I turns Iin the opposite direction the 'revoluble Lingbolt when released causing the same to ,lcol ternal gear wherebyv when thedrive shaftis automaticallyoperative upon firing the fuse r connecting the saidjdrive' shaft Withfthe in i when the drive: shaft turns in the ,opposite lw,

tact 'with the revoluble 'memtemmtii for-actuating the lockingmember icausi'ngfj member fornthe release of the striker-.16 Ina projectile of-t-heltype describechga} f dr ve shaft, ajrevoluble gear, a striker,=ineansl connecting 1the.,.drive, shaft and-airevoluble i gear wherebyjwhen the drive shaft turned; M lnflone'directlon the-revolu-ble gear ris turned I gear *is turned thereby a predetermined :por tion ofarevolution'toldetermine the moment of release of thestriker, .a'lockingboltfor sa I normally maintainingthe striker in an xiii- V g operative position, -means for. maintaining i thelockingbol-t outlof contact with the revs f; oluble gear until just beforethe striker released, and mea-nsyfor actuating, the lock 'isfii operate with the; revoluble ge ar: in re '3;,lfn aprojectile oftheftypedescribed,a 'clriveshaft, an internal gear having v n there n, a striker,- a lockingbolt for normally j 'maintaining the strike'rin-an'initialinopera tive position and' when released to enterthe recess inthe 1nternal gearto free the striker, a means connecting the drlve shaft' and the in- 'g95v;

turned in one. direction the internalgear is"; w V turned to a set'position and when the drive; shaft 13111115111 the opposite direction the'ing .ternal-gear is turnedtherebya predetermined 160 r portion of a revolution in the other direction; i

striker, means formaintainingfthelocking1f"; bolt out'of" contact with the internalgear' I V untilj -'.jus tbefore ;the striker registers with "j the recess in the internalgear, a device by which the aforesaid means is freleas'e d' just before the locking bolt registers with the: i

recessin. the internalgear, andme'ans, operin the recess in tliecrown piece, a'droppln'g formaintaining thefsaid lockingbolt in its initial position, thefsaid drop plug {being V I to free itself from thesaid locking bolt, meansi 5 ternal gearjof the crown piece whereby- "when; the drive shaft is Tlllllliedlll one d1rection the? crown piece s turned to a set pos tionanddirection the crown piece tnrnse predetermined portion of a revolution in theother clirectionuntil the free end of thelocking bolt ment thereof, ancl'means opereti e "inomen I i tarily 'before'the end of the locking bolt registers'witli the recess i I leasing-V the locking bolt =ancl actuating the in the crown'piece for re 7 same to causejthe 'free end thereof to enterthe said recess in the crownpiecetherebyire 15 ing'the lockingbolt from the striker, f 5. In 21 pro ectile of the type 7 described a drive shaft a crownbiece'havin recess 9 i b V therein and nrovicle cl with internal ear teeth &3

astriker, a'pivotedlocking bolt normally in engagement with the striker toginaintain the" same in an initial inoperative position'and having a freev encl adapted to engage in'the recess in the said crown iece adroy )lii V b fori'naiiitaining the'saicl locking bolt-in its initial position, the said drop piug'being auto-V matically operative upon firingthe' fuse to free itself froin thersaicl locking bolt, means connecting thesaid drive with the internal gear-of the crown piece-whereby when the drive shaft is turned intone direction the crowni'piec'e is turned toa set position and whenfthe drive shaft turns in the opposite clireotion the crown piece turns apredetermined portion of a revolution in the other direction until the free end of the looking bolt. isin position to enge e in the recess in the crown piece, means for maintaining the locking bolt in a positionin which its free end does not conta'etlwith the crownpiece luring the major portion o f'the'return movement thereof, means operative momentarily before the-end of vthe locking bolt registers with the recess in the crown piece for releasmg the locking bolt and actuating the same tofcausethe free end thereof to enter the said recess in the crown piece t hei'eby freeing the locking bolt from the striker, and means-for actuating the striker afterthe same has been. freed from the lock ng bolt;

In testimony whereof Iaiiix my si-gn'atnre.

' ANDRE VAR UDQ 

